Door lock

ABSTRACT

A tamper-proof door lock having a beveled latch bolt which is extended by spring pressure for latching engagement with a keeper plate on the door jamb upon closing of the door and is retractable by rotation of the door handle to open the door. The lock embodies locking means, releasible by door handle rotation, for locking the latch bolt against retraction by insertion of a shim or blade between the door edge and keeper plate. The latch bolt of the described lock is locked in its extended latching position by extension of a locking member carried by the bolt to a locking position behind the keeper plate. Rotation of the door handle to open the door effects initial retraction of the locking member and then retraction of the latch bolt.

' Unite States [4 1 Oct. 14, 1975 DOOR LOCK Thomas J. Dugan, 2501 S. ElCamino Real No. 206, San

Clemente, Calif. 92672 22 Filed: Mar. 22, 1974 [21] Appl. No.: 453,585

[76] Inventor:

[56] References Cited UNITED STATES PATENTS 5/1902 Fogel 292/169.l412/1955 Gresham et al 292/192 X Primary Examiner-Richard E. MooreAttorney, Agent, or FirmBoniard I. Brown [5 7] ABSTRACT A tamper-proofdoor lock having a beveled latch bolt which is extended by springpressure for latching engagement with a keeper plate on the door jambupon closing of the door and is retractable by rotation of the doorhandle to open the door. The lock embodies locking means, releasible bydoor handle rotation, for locking the latch bolt against retraction byinsertion of a shim or blade between the door edge and keeper plate. Thelatch bolt of the described lock is locked in its extended latchingposition by extension of a locking member carried by the bolt to alocking position behind the keeper plate. Rotation of the door handle toopen the door effects initial retraction of the locking member and thenretraction of the latch bolt.

11 Claims, 8 Drawing Figures US, Patent ot.14,1975 sheetzof 3,912,310

US. Patsnt Oct. 14, 1975 Sheet 3 of3 3,912,310

DOOR LOCK BACKGROUND OF THE INVENTION 1. Field of the Invention Thisinvention relates generally to door locks and more particularly to aburglarproof lock for swinging entry doors.

2. Discussion of the Prior Art Generally speaking this invention relatesto door locking devices of the kind which comprise a door lock properand a keeper plate and are used on entry doors that are hinged along onevertical edge for swinging between open and closed positions. Whenclosed, the opposite or outer door edge is situated in closedconfronting relation to a door jamb which mounts the keeper plate. Thisdoor jamb may be either a fixed upright member of the door frame or, inthe case of double hinger doors, the vertical outer edge of a secondhinged door that is normally secured in closed position by means ofslide bolts on the door entering sockets in the upper and lower portionsof the frame.

The door lock proper is installed in a recess in the door along itsouter edge and includes a beveled latch bolt which is normally extendedby spring pressure beyond the edge. When the door closes, the beveledouter end of the bolt engages the keeper plate on the door jamb in sucha way that the plate retracts the bolt against its spring biassufficiently to allow the bolt to ride over the plate. Upon arrival ofthe door at the fully closed position, the bolt enters an opening in thekeeper plate to secure the door in closed position. Retraction of thelatch bolt to open the door is accomplished by rotation of the doorhandle. In the case of entry doors of the type with which this inventionis concerned, the outside door handle is equipped with a key lock whichnormally locks the handle against turning to open the door.

Existing door locking devices of this kind are deficient in that anintruder may quite easily gain entrance by simply inserting animplement, such as a shim or blade, between the door and jamb andagainst the beveled end of the latch bolt to force thr latter from thekeeper plate against the spring pressure on the bolt, thereby permittingthe door to be opened. This shortcoming of the locking devices, ofcourse, has been recognized in the past and has been avoided by the useof dead bolt locks, night chains, and the like. These methods ofpreventing entry b an intruder are not totally satisfactory, however,since they require the use of two separate locking devices and, in thecase of a night chain, can only be used from the inside.

SUMMARY OF THE INVENTION This invention provides an improved lock fordoor locking devices of the class described which prevents intrusiveentry in the manner explained above. To this end, the door lock isequipped with means for locking the latch bolt in its extended positionof latching engagement with the keeper plate in such a way that the boltcannot be forced out of engagement with the plate until released fromthe inside of the door.

In the particular door lock described, the bolt locking means comprisesa locking member carried by the outer end of the latch bolt. Thislocking member is mormally retracted flush with the bolt to prevententrance of the bolt into the keeper plate opening. The

locking member is then extendable laterally of the bolt,

by an actuating member at the inside of the door, to a locking positionbehind the keeper plate wherein the member locks the bolt againstretraction from the plate opening. The locking member is retracted torelease the latch bolt for retraction by rotating the inner door handlethrough an initial angle; continued rotation of the handle retracts thebolt from the keeper plate to permit opening of the door.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a section through a doorlock according to the invention;

FIG. 2 is a section taken on line 22 in FIG. 1;

FIG. 3 is a section taken on line 33 in FIG. 1;

FIG. 4 is a section taken on line 4-4 in FIG. 1;

FIG. 5 is a section taken on line 55 in FIG. 1;

FIG. 6 is a section taken on line 66 in FIG. 1;

FIG. 7 is a section similar to FIG. 1 showing the latch bolt locked inextended position; and

FIG. 8 is an exploded perspective view of the lock.

DESCRIPTION OF THE PREFERRED EMBODIMENT The drawings illustrate a lock10 according to the invention installed in a recess 12 in the outer edge13 of a hinged door 14 for cooperation with a keeper plate 16 (FIG. 7)on the door jamb 18 to lock the door in closed position. As notedearlier, this door jamb may be a fixed upright member of the door frameor, in the case of double doors, the outer edge of a second, normallylocked door.

Generally speaking, the lock 10 includes a housing 20 containing a latchbolt 22 which is movable longitudinally of the housing between itsextended position of FIGS. 1, 2 and 7 and a retracted position. In itsextended position, the outer end of the latch bolt projects beyond theadjacent end of the housing 20 and the outer door edge 13 for engagementin a bolt receiving opening 24 in the keeper plate 16 to latch the doorclosed. Accordingly, the extended position of the latch bolt is itslatching position. When retracted, the outer end of the latch bolt issubstantially flush with the door edge and the door is free to open andclose.

Latch bolt 22 is urged to its extended latching position by spring means26 acting between the bolt and housing 20. The door has knobs or handles28 (only one shown) which are operatively connected to the latch bolt toretract the latter against spring pressure upon rotation of eitherhandle. One handle, generally the outside handle, embodies a key lockfor locking the handle against turning to retract the latch bolt untilreleased by the proper key. The other or inside handle is freelyrotatable to open the door. This latter handle 28 is shown in phantomlines in FIGS. 1 and 6.

The outer end of the latch bolt 22 is beveled or rounded in the usualway, as shown at 30 in FIG. 2. In the event the door 14 is closedwithout retraction of the bolt by door handle rotation, the beveledsurface 30 of the bolt engages an edge of the keeper plate 16 as thedoor approaches closed position. The plate produces on the bolt acamming force which retracts the bolt against spring pressuresufficiently to enable the bolt to ride over the plate. Upon the doorreaching fully closed position, the bolt snaps into the keeper plateopening 24 to latch the door closed.

As noted earlier, with conventional door locks of this general type, itis a fairly easy task for an intruder to gain entrance by inserting ablade-like implement between the outer door edge and door jamb andurging the implement against the beveled end of the latch bolt toretract the latter from the keeper plate. According to a primary featureof this invention, the lock is provided with locking means 32 forlocking the latch bolt 22 against retraction from the keeper plate 16 bysuch an implement and thereby preventing intrusive entry in the mannerexplained. This bolt locking means includes an actuator 34 for settingthe locking means in its locking condition and means 36 for releasingthe locking means. In the particular lock shown, the bolt locking means32 comprises a locking member 38 carried by the outer end of the latchbolt 22 and extendable by the actuator 34 to a locking position (FIG. 7)behind the keeper plate 16. The lock releasing means 36 is operable byinitial rotation of either door handle 28 to retract the locking memeber38 to its position of FIG. 1, wherein the latch bolt is free to retractfrom the keeper plate 16. Continued rotation of the door handle retractsthe bolt from the keeper plate to permit opening of the door 14.

The illustrated door lock 10 will now be described in greater detail.The lock housing comprises a sleeve 40 joined at its outer end to aflange 42 and face plate 44 with mounting screw holes 46 and closed atits inner end by a wall 48. Face plate 44 has a rectangular opening 50aligned on the axis of the housing sleeve 40. Latch bolt 22 is movablethrough this face plate opening and has an inner flange 52 which isengageable with the inner side of the face plate to limit extension ofthe bolt through the opening to the bolt position of FIGS. 1 and 2.

Latch bolt 22 is supported for extension and retraction in the lockhousing 20 by slide means 54 including a pair of bearing posts 56 on thebolt, a generally yokeshaped slide frame 58 and a slide plate 60.Bearing posts 56 are rigidly joined to the inner end of the latch bolt22 and extend inwardly or rearwardly through the housing 20 parallel toits longitudinal axis. Slide frame 58 is movable longitudinally in thehousing and includes a plate 62 at the outer end of the frame in atransverse plane of the housing. This plate is sized to slide in thehousing and has bores 63 slidably receiving the latch bolt bearing posts56. Posts 56 extend beyond the rear side of the plate and mount snaprings 56a which retain the plate against rearward movement from theposts. Integrally joined to and extending rearwardly from the plate 62are a pair of legs 64 parallel to the longitudinal axis of the housing.These legs slide in slots 66 in the slide plate 60. Slide plate 60 isalso sized to slide in the lock housing. As shown best in FIGS. 2 and 8,opposite sides of the inner or rear end of the housing 20 are inset toform forwardly or outwardly facing stop shoulders 68 against which theslide plate 60 normally seats to position the plate longitudinally inthe housing.

As noted earlier, latch bolt 22 is urged to its extended latchingposition by spring means 26. These spring means include a first set ofsprings 70 and a second set of springs 72. Springs 70 surround the latchbolt bearing posts 56 and seat at their outer ends against the latchbolt and at their inner ends against the slide frame plate 62. Springs72 are located between and seat against the latter plate and slide plate60. The outer ends of these latter springs fit over the projecting innerends of the posts 56. The inner ends of the springs engage overpositioning dimples 74 formed on the slide plate 60.

From the description to this point, it is apparent that the springs 70,72 urge the latch bolt 22 outwardly to its extended position of FIG. 2,the slide frame 58 outwardly toward the latch bolt to the frame positionshown in the latter figure, and the slide plate 60 inwardly into seatingengagement with the lock housing shoulders 68. The latch bolt and slideframe are movable inwardly relative to the housing against the pressureof the springs, and the slide plate is movable outwardly relative to thehousing, also against the spring pressure. The latch bolt 22 normallyoccupies its extended position. When the door 14 is closed, the beveledor rounded surface 30 of the bolt initially engages the leading edge ofthe keeper plate 16 and is cammed inwardly by the plate to retractedposition to permit the bolt to ride over the keeper plate. When the doorreaches fully closed position, the latch bolt is urged by springpressure into the keeper plate opening 24 to lock the door closed.

As noted earlier, the latch bolt 22 is retracted against spring pressureto open the door 14 by rotation of the door handles 28. To this end, theinner handle (shown) is fixed, to a shaft 76 which extends through therear or inner end of the lock housing 20, transverse to its longitudinalaxis. The shaft is rotatably supported in the usual way to turn on itslongitudinal axis. The outer door handle 28 is coupled to the shaft,also in the usual way, such that the latter handle may be locked againstturning by its key lock without preventing rotation of the inner handle.When the outer handle is unlocked, it may be turned to rotate the shaft76.

Fixed to the handle shaft 76 within the housing 20 is a collar 78 havinga pair of integral radial projections or lobes 80 and 82 with generallycircularly rounded outer ends. The purpose of lobe 80 will be explainedpresently. Lobe 82 projects through a longitudinal slot 84 in the upperleg 64 (as viewed in FIG. 1) of the slide frame 58. The rear edge ofthis slot is turned upwardly to form a seating surface 86 for engagementby the lobe. Clockwise rotation of the shaft 76 from its position ofFIG. 1 by rotation of either door handle urges the lobe 82 against theslide frame surface 86 to move the slide frame 58 and thereby the latchbolt 22 inwardly or rearwardly (i.e., to the right in FIG. 1) relativeto the lock housing 20. Theus, clockwise rotation of the handlesretracts the latch bolt to permit opening of the door 14. Release of thehandles effects return of the parts to their positions of FIG. 1 byspring pressure.

From the earlier discussion, it will be recalled that a primary featureof the invention resides in locking means 32 for releasably locking thelatch bolt 22 in its extended latching position to prevent intrusiveentry. Locking means 32 comprises the locking member 38 carried by theouter end of the bolt for movement to and from a locking position behindthe keeper plate 16. This locking member is a cylindrical pin whichslides in a normally vertical transverse bore 88 in the latch bolt 22.Associated with this lock pin is a telescoping arm 90 including a pairof slidably interfitting arm members 92, 94. The outer arm member 92 hasa flat blade portion 96 rigidly joined at its front end to a collar 98.Collar 98 seats coaxially on the upper end of and is firmly attached bya screw 100 to the lock pin 38. The blade portion 98 of the arm member92 extends laterally inward from the lock pin 38 and slidably through aslot 102 in the lock bolt 22 in the plane of the axis of the pin bore88. Projecting laterally from the inner end of the blade portion 96 areribs 104 located in a plane normal to the plane of and containing thelongitudinal axis of the blade portion. Blade portion 96 extendsinwardly through a vertical slot 106 in the front plate 62 of the slideframe 58.

The inner member 94 of the telescoping arm 90 has an outer flatblade-like portion 108 with a vertical longitudinal slot 110 whichslidably receives the blade portion 96 of arm member 92 and laterallyopening slots 112 which slidably receive the ribs 104 on the lattermember. Thus, the arm members 92, 94 are slidably keyed to one anotherfor relative longitudinal extension and retraction. On the inner end ofthe inner arm member 94 is an enlarged integral block-like head 114which fits within a vertical slot 1 16 in the slide plate 60. Enteringopposite sides of the head 114 are grooves 118 which slidably receivethe vertical edges of the plate slot 1 16. From this description, it isapparent that the telescoping arm 90 and the lock pin 38 are slidablysupported by the slide plate 60 for movement as a unit in the axialdirection of the pin. The lock bolt 22, lock pin 38, and outer member 92of the telescoping arm 90 are movable as a unit relative to the innerarm member 94 in the longitudinal direction of the latter member and thelock housing 20.

Projecting from opposite sides of the telescoping arm inner head 114 areextensions 120, 122. Extension 120 is engaged by a wire spring 124 whichis secured to the inner side of the slide plate 60 and fits in a slot126 in the extension. This spring urges the telescoping arm 90 upwardlyin the slide plate slot 116 to the position of FIG. 1 wherein the lockpin is fully retracted into the latch bolt 22. The telescoping arm andlock pin are movable downwardly against the bias of the spring 124 tothe position of FIG. 7, wherein the lock pin projects below theunderside of the latch bolt.

The telescoping arm 96 and lock pin 38 are moved from the retractedposition of FIG. 1 to the extended position of FIG. 7 by the lockactuator 34. This lock actuator comprises a lever 128 having a centraltransverse journal 130 which is rotatable in a bracket 132 fastened byscrews to the inner side of a cover plate 134 for the inner door handle28. This cover plate seats against the inner side of the door 14 and isfixed to the door in the usual way. Handle shaft 76 extends rotatablythrough the plate for connection to the inner door handle. Extendingoutwardly from the journal 130, through an opening 136 in the coverplate 134 is a lever arm 138. Extending inwardly through an opening 140in the lock housing is a lever arm 142. The inner end of the latter armhas a rounded portion 144 for engaging the inner lateral extension 122on the telescoping arm 90.

The actuator lever 128 is mounted by the bracket 132 to pivot on an axisparallel to the longitudinal axis of the lock housing 20. Upwardrotation of the outer arm 138 of the lever rotates the inner lever arm142 downwardly against the extension 122 of the telescoping arm 90,thereby moving the arm and the latch bolt lock pin 38 downwardly againstthe action of spring 124. Thus, the lock pin is movable to its extendedposition of FIG. 7 by rotating the outer arm 138 of the actuator lever128 upwardly.

Fixed to the inner head 1 14 of the telescoping arm 90 and projectingbelow the head is a resilient catch 146 having a locking shoulder 148.During downward extension movement of the telescoping arm and the lockpin 38 to their extended position of FIG. 7 by the actuator lever 128,in the manner just explained, catch" 146 enters an opening 150 in thelower leg 64 of the slide frame 58, and the catch shoulder 148 snapsunder the edge of the opening, as shown in FIG. 7, to latch the lock pinand telescoping arm in their lower extended position. The lower end ofcatch 146 is beveled, as shown, such that the catch is deflected intoopening and then snaps into latching engagement under the edge of theopening.

As noted earlier, the handle shaft collar 78 has a lobe 80. When thetelescoping arm 90 and lock pin 38 occupy their upper retractedpositions of FIG. 1 and the handle shaft 76 occupies its position of thelatch figure, lobe extends longitudinally of the lock housing 20 into aninwardly and upwardly opening recess 152 in the inner end head 114 ofthe telescoping arm and is located above the horizontal longitudinalplane P of the housing which contains the shaft axis. Recess 152 haslaterally and longitudinally facing walls 154, 156. Handle shaft 76 isurged counter-clockwise by a spring (not shown) which retains lobe 80 inseating contact with recess wall 154. The springs 70, 72 retain therecess wall 156 in seating contact with the lobe 80. It should be notedhere that in the position of the lock parts shown in FIG. 1, the slideplate 60 is spaced a slight distance outwardly of the lock housing 20from the housing shoulders 68. Accordingly the springs 70, 72 retain therecess wall 156 in contact with the lobe 80, as just stated. When thelock actuator lever 128 is rotated to depress the telescoping arm 90 andextend the lock pin 38 below the latch 22, the handle shaft spring urgesthe handle shaft 76 counterclockwise to the position of FIG. 7 to retainthe lobe 80 in contact with the recess wall 154 and the springs 70, 72urge the slide plate 60 inwardly to the housing shoulders 68 to retainthe recess wall 156 in contact with the lobe.

Referring to FIG. 7, it will be seen that in the illustrated position ofthe lobe 80, the latter is located below the plane P of the handle shaftaxis. Accordingly, during clockwise rotation of the handle shaft 76 fromthe position of FIG. 7, the initial rotational motion of the lobe 80 hasa vertical upward component toward the plane P and an outward horizontalcomponent toward the recess wall 156. This horizontal component pressesthe lobe against the latter recess wall to move the rear member 94 ofthe telescoping arm 90 and the slide plate 60 outwardly toward the outerend of the lock housing 20. Such outward movement of the arm member andplate occurs relative to the slide frame 58 and releases the shoulder148 of the telescoping arm latch 146 from the lower slide frame leg 64.The spring 124 then moves the telescoping arm 90 and lock pin 38upwardly to their retracted positions of FIG. 1 and rotates the handleshaft 76 to its position of the latter figure, against the bias of thehandle spring.

The operation of the lock 10 will now be explained, assuming the lockparts are initially in their positions of FIG. 1 and the door 14 isopen. When the door is closed, the latch bolt 22 rides over the keeperplate 16 and then snaps into the keeper plate opening 24 to latch thedoor closed. The latch bolt is retracted to open the door by rotatingeither door handle 28 clockwise in FIG. 1 to retract the slide frame 58to the right against the pressure of springs 72 by pressure of the onthe latch bolt bearing posts 56.

The latch bolt 22 is locked in its extended position of engagement withthe keeper plate 16 by rotating the lock actuator lever 128 in adirection to depress the telescoping arm 90 to its lower position ofFIG. 7. This action extends the lock pin 38 behind the keeper plate tolock the latch bolt against retraction, as shown in FIG. 7. It will beunderstood that a clearance space for the lock pin is provided behindthe keeper plate. The lock pin is latched in its extended position bylatching engagement of the telescoping arm catch 146 in the lower legopening 150 of the slide frame 58.

Release of the latch bolt 22 for retraction to open the door 14 isaccomplished by clockwise rotation of the door handles from the positionof FIG. 1. This handle rotation initially releases the catch 146 fromthe slide frame 58 in the manner explained earlier and then retracts theslide frame and latch bolt.

What is claimed as new in support of Letters Patent is' a housing,

a latch bolt having a beveled outer end and movable longitudinally insaid housing between an extended position wherein said outer bolt endprojects beyond one end of said housing for latching engagement with akeeper plate on the door jamb to latch the door closed and a retractedposition wherein said outer bolt end is disposed to clear the keeperplate and release the door for opening,

spring means urging said bolt to extended position,

a rotatable handle shaft extending transversely of said housing,

means connecting said shaft and bolt for retraction of the bolt by shaftrotation, and

means for selectively releasably locking said bolt in extended positionagainst retraction by a force applied to the outer bolt end comprising alocking member on the outer end of said bolt movable between a retractedposition wherein said bolt is freely movable into and from latchingengagement with the keeper plate and an extended position wherein themember projects from the bolt for locking engagement behind the keeperplate, and actuating means for effecting selective extension andretraction of said locking member independently of extension andretraction of said bolt in a manner which permits extension andretraction of said bolt while said locking member remains in retractedposition and extension and retraction of said locking member while saidbolt is in extended position.

2. A door lock according to claim 1, wherein:

said locking member comprises a lock pin slidable in the bolt to andfrom an extended position wherein one end of the pin projects beyond oneside of the bolt for locking engagement behind the keeper plate.

3. A door lock according to claim 1 wherein:

said actuating means comprises means operable by 65 l. A lock for ahinged door comprising: 25

said actuating means comprises an actuator at one side of said door formoving said locking member to locking position independently of handleshaft rotation, and means operable by handle shaft rotation foreffecting retraction of said lockin m from locking position.

5. A door lock according to claim 3 wherein:

said locking means includes a catch for releasably latching said lockingmember in said locking position, and

said retracting means operable by handle shaft rotation comprises meansfor releasing said catch upon shaft rotation, and a spring forretracting said locking member upon release of said catch.

6. A lock for a hinged door comprising:

a housing,

a latch bolt having a beveled outer end and movable longitudinally insaid housing between an extended position wherein said outer bolt endprojects beyond one end of said housing for latching engagement with akeeper plate on the door jamb to latch the door closed and a retractedposition wherein said outer bolt end is disposed to clear the keeperplate and release the door for opening,

spring means urging said bolt to extended position,

a rotatable handle shaft extending transversely of said housing,

means connecting said shaft and bolt for retraction of the bolt by shaftrotation, and

means for releasably locking said bolt in extended position againstretraction by a force applied to the outer bolt end comprising a lockingpin slidable in the outer end of said bolt for movement laterally of thebolt between an extended position wherein one end of the pin projectsbeyond one side of the bolt for locking engagement behind the keeperplate and a retracted position flush with the bolt, a telescoping armextending longitudinally through the housing and a slot in said bolt andincluding an outer member fixed to said bolt and an inner memberslidably engaging the outer member, whereby said latch bolt and outerarm member are movable in unison relative to said inner arm member inthe direction of extension and retraction of the bolt, and said arm andpin are movable in unison in the direction of extension and retractionof the pin relative to the bolt, means supporting said inner arm memberin said housing for movement in the latter direction, and means operableon said inner arm member for moving said inner member in the latterdirection to position said pin in extended and retracted positions.

7. A door lock according to claim 6 wherein:

said means operable on said arm comprises a spring for urging said armin a direction to retract said pin, an actuator for moving said arm in adirection to extend said pin against the pressure of the latter spring,a catch for latching said arm in a position wherein said pin isextended, and means for releasing said catch.

8. A door lock according to claim 7 wherein:

said catch releasing means is operable by handle shaft rotation.

9. A door lock according to claim 8 wherein:

said means connecting said handle shaft and bolt comprises a slide framein and movable longitudinally of said housing, means connecting saidlatch bolt and frame for retraction of said bolt relative to said frameby an inward force on the outer end of said bolt and retraction of saidbolt with said frame by an inward force on said frame, and means on saidhandle shaft engageable with said frame for retracting said frame andbolt by shaft rotation.

said catch is engageable with said frame to latch said lock pin inextended position, and

said catch releasing means comprises means for effecting relativelongitudinal movement of said arm and frame by handle rotation torelease said catch from said frame.

10. In combination:

a door hinged within a door opening for swinging to and from a closedposition wherein the outer door edge is disposed in close confrontingrelation to a door jamb,

a keeper plate mounted on said jamb,

a door lock mounted on said door along said door edge including a latchbolt having a beveled outer end and movable longitudinally between anextended position wherein said outer bolt end projects beyond said dooredge for latching engagement with said keeper plate when said door isclosed and a retracted position wherein said outer bolt end clears saidkeeper plate to permit opening the door, spring means for urging saidbolt to extended position, means including rotatable door handles forretracting said bolt against spring pressure by handle rotation, andmeans for selectively releasably locking said bolt in extended positioncomprising a locking member on the outer end of said bolt movablebetween a retracted position wherein said bolt is freely movable intoand from latching engagement with the keeper plate and an extendedposition wherein the member projects from the bolt for lockingengagement behind the keeper plate, and actuating means for effectingselective extension and retraction of said locking member independentlyof extension and retraction of said bolt in a manner which permitsextension and retraction of said bolt while said locking member remainsin retracted position and extension while said bolt is in extendedposition.

11. The combination according to claim 10 wherein:

said actuating means comprises an actuator at one side of said door formoving said locking member to locking position independently of doorhandle rotation, and means operable by door handle rotation foreffecting retraction of said locking member from locking position.

1. A lock for a hinged door comprising: a housing, a latch bolt having abeveled outer end and movable longitudinally in said housing between anextended position wherein said outer bolt end projects beyond one end ofsaid housing for latching engagement with a keeper plate on the doorjamb to latch the door closed and a retracted position wherein saidouter bolt end is disposed to clear the keeper plate and release thedoor for opening, spring means urging said bolt to extended position, arotatable handle shaft extending transversely of said housing, meansconnecting said shaft and bolt for retraction oF the bolt by shaftrotation, and means for selectively releasably locking said bolt inextended position against retraction by a force applied to the outerbolt end comprising a locking member on the outer end of said boltmovable between a retracted position wherein said bolt is freely movableinto and from latching engagement with the keeper plate and an extendedposition wherein the member projects from the bolt for lockingengagement behind the keeper plate, and actuating means for effectingselective extension and retraction of said locking member independentlyof extension and retraction of said bolt in a manner which permitsextension and retraction of said bolt while said locking member remainsin retracted position and extension and retraction of said lockingmember while said bolt is in extended position.
 2. A door lock accordingto claim 1, wherein: said locking member comprises a lock pin slidablein the bolt to and from an extended position wherein one end of the pinprojects beyond one side of the bolt for locking engagement behind thekeeper plate.
 3. A door lock according to claim 1 wherein: saidactuating means comprises means operable by rotation of said handleshaft for retracting said member from locking position.
 4. A door lockaccording to claim 1 wherein: said actuating means comprises an actuatorat one side of said door for moving said locking member to lockingposition independently of handle shaft rotation, and means operable byhandle shaft rotation for effecting retraction of said locking memberfrom locking position.
 5. A door lock according to claim 3 wherein: saidlocking means includes a catch for releasably latching said lockingmember in said locking position, and said retracting means operable byhandle shaft rotation comprises means for releasing said catch uponshaft rotation, and a spring for retracting said locking member uponrelease of said catch.
 6. A lock for a hinged door comprising: ahousing, a latch bolt having a beveled outer end and movablelongitudinally in said housing between an extended position wherein saidouter bolt end projects beyond one end of said housing for latchingengagement with a keeper plate on the door jamb to latch the door closedand a retracted position wherein said outer bolt end is disposed toclear the keeper plate and release the door for opening, spring meansurging said bolt to extended position, a rotatable handle shaftextending transversely of said housing, means connecting said shaft andbolt for retraction of the bolt by shaft rotation, and means forreleasably locking said bolt in extended position against retraction bya force applied to the outer bolt end comprising a locking pin slidablein the outer end of said bolt for movement laterally of the bolt betweenan extended position wherein one end of the pin projects beyond one sideof the bolt for locking engagement behind the keeper plate and aretracted position flush with the bolt, a telescoping arm extendinglongitudinally through the housing and a slot in said bolt and includingan outer member fixed to said bolt and an inner member slidably engagingthe outer member, whereby said latch bolt and outer arm member aremovable in unison relative to said inner arm member in the direction ofextension and retraction of the bolt, and said arm and pin are movablein unison in the direction of extension and retraction of the pinrelative to the bolt, means supporting said inner arm member in saidhousing for movement in the latter direction, and means operable on saidinner arm member for moving said inner member in the latter direction toposition said pin in extended and retracted positions.
 7. A door lockaccording to claim 6 wherein: said means operable on said arm comprisesa spring for urging said arm in a direction to retract said pin, anactuator for moving said arm in a direction to extend said pin againstthe pressure of the latter Spring, a catch for latching said arm in aposition wherein said pin is extended, and means for releasing saidcatch.
 8. A door lock according to claim 7 wherein: said catch releasingmeans is operable by handle shaft rotation.
 9. A door lock according toclaim 8 wherein: said means connecting said handle shaft and boltcomprises a slide frame in and movable longitudinally of said housing,means connecting said latch bolt and frame for retraction of said boltrelative to said frame by an inward force on the outer end of said boltand retraction of said bolt with said frame by an inward force on saidframe, and means on said handle shaft engageable with said frame forretracting said frame and bolt by shaft rotation. said catch isengageable with said frame to latch said lock pin in extended position,and said catch releasing means comprises means for effecting relativelongitudinal movement of said arm and frame by handle rotation torelease said catch from said frame.
 10. In combination: a door hingedwithin a door opening for swinging to and from a closed position whereinthe outer door edge is disposed in close confronting relation to a doorjamb, a keeper plate mounted on said jamb, a door lock mounted on saiddoor along said door edge including a latch bolt having a beveled outerend and movable longitudinally between an extended position wherein saidouter bolt end projects beyond said door edge for latching engagementwith said keeper plate when said door is closed and a retracted positionwherein said outer bolt end clears said keeper plate to permit openingthe door, spring means for urging said bolt to extended position, meansincluding rotatable door handles for retracting said bolt against springpressure by handle rotation, and means for selectively releasablylocking said bolt in extended position comprising a locking member onthe outer end of said bolt movable between a retracted position whereinsaid bolt is freely movable into and from latching engagement with thekeeper plate and an extended position wherein the member projects fromthe bolt for locking engagement behind the keeper plate, and actuatingmeans for effecting selective extension and retraction of said lockingmember independently of extension and retraction of said bolt in amanner which permits extension and retraction of said bolt while saidlocking member remains in retracted position and extension while saidbolt is in extended position.
 11. The combination according to claim 10wherein: said actuating means comprises an actuator at one side of saiddoor for moving said locking member to locking position independently ofdoor handle rotation, and means operable by door handle rotation foreffecting retraction of said locking member from locking position.